Portion of an off-highway truck



FIG. 1 is a front view of our new design;

FIG. 2 is a left view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right view thereof;

FIG. 5 is a top view thereof;

FIG. 6 is a left, front perspective view thereof; and,

FIG. 7 is a right, front perspective view thereof.

The bottom view does not form part of the claimed design and therefore is not disclosed.

The elements depicted in dashed lines form no part of the ornamental design. 

The ornamental design for a portion of an off-highway truck, as shown and described. 